1. Field of the Invention
The present invention relates to an improvement in a fluid transmitting device with a lock-up clutch, comprising: a turbine impeller having a shell; and a lock-up clutch including: a clutch piston; an annular spring accommodation groove formed in the clutch piston to accommodate a plurality of annularly-arranged damper springs; a plurality of first power transmission claws inserted between adjacent ones of the damper springs and secured to the clutch piston; a plurality of second power transmission claws inserted between adjacent ones of the damper springs so as to face the first power transmission claws, and having support portions which are connected to an outer peripheral surface of the shell of the turbine impeller via a weld formed by laser beams.
2. Description of the Related Art
Such a fluid transmitting-device with a lock-up clutch is already known, as disclosed in Japanese Patent No. 3001853.
As described above, when the support portions of the second power transmission claws are welded by laser beams on the outer peripheral surface of the shell of the turbine impeller, no spatter occurs as in TIG welding and no cladding such as a weld bead is formed, thus eliminating the need for finishing after welding as well as providing good appearance and cost reduction.
In the above-mentioned device of Japanese Patent No. 3001853, the support portions of the second power transmission claws and the shell of the turbine impeller are welded together by applying laser beams to an inner corner of a portion where they overlap. In this case, however, it is difficult to perform a visual inspection as to whether the welding condition is good or not.